Bloomberg offers a window into world wealth accumulation by citing this Boston Consulting Group study of the asset managers and their clients. Turns out there is 12.5 million households with liquid, investible wealth of $1m or more. That’s a big population:

The U.S. had the most $1 million-plus households, with 5.2 million, followed by Japan and China. […] Singapore also had the highest proportion of millionaire households at 15.5 percent, followed by Switzerland and Qatar. Saudi Arabia had the highest concentration of ultra-high-net- worth households, which are those with more than $100 million in assets, at 18 per 100,000. Switzerland was second, and Hong Kong was third. […] Singapore millionaires rose by almost 33 percent after jumping about 40 percent a year earlier.

World’s Wealthy Rose by 12%: Boston Consulting (Bloomberg)